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US3753094A - Ohmmeter for measuring the internal resistance of a battery and directly reading the measured resistance value - Google Patents

Ohmmeter for measuring the internal resistance of a battery and directly reading the measured resistance value Download PDF

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US3753094A
US3753094A US3753094DA US3753094A US 3753094 A US3753094 A US 3753094A US 3753094D A US3753094D A US 3753094DA US 3753094 A US3753094 A US 3753094A
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circuit
dc
voltage
battery
constant
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H Furuishi
Y Iida
T Fukuoka
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Panasonic Corp
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Panasonic Corp
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/36Apparatus for testing electrical condition of accumulators or electric batteries, e.g. capacity or charge condition
    • G01R31/3644Various constructional arrangements
    • G01R31/3662Various constructional arrangements involving measuring the internal battery impedance, conductance or related variables

Abstract

An ohmmeter for measuring the internal resistance of a battery by an A.C. method. The output of a DC power circuit is converted into an alternating current of prescribed frequency through a DC - AC conversion circuit. The alternating current flows through a battery by way of a DC blocking device and the voltage drop due to the internal resistance of the battery is introduced into an AC voltmeter circuit. The internal resistance of the battery is indicated at the indicating portion of the AC voltmeter circuit so that it is read directly.

Description

Field of Search ..324/29.5, 62, 64; Y 340/249; 136/182 United States Patent [1.91 [111 3,753,094 Furuishi et al. Aug. 14, 1973 OHMMETER FOR MEASURING THE [56] References Cited INTERNAL RESISTANCE OF A BATTERY UNITED STATES PATENTS AND DIRECTLY READING THE MEASURED 2 811 446 mm Wann 324/64 RESISTANCE VALUE 2,896,159 7/1959 Webster 324/64 [75] Inventors: Haruhba Flll'lllihi, Suita'; Yasunobu FOREIGN PATENTS "OR APPIJCATIONS Iida, Osaka; Toshiaki Fukuoka, I Hirakata, a of Japan 7 901,080 l/l954 Germany 324/62 [73] Assignee: Matsushita Electric Induatrial Co. primary Examine,- Rben LCm-coran Osaka Japan Attorney-Stevens, Davis, Miller & Mosher [22] Filed: July 24, 1972 21 Appl. No.: 274,809 [571 ABSTRACT An ohmmeter for measuring the internal resistance of 3 3"? a battery by an A.C. method. The output of a DC [6 Cgmtanuatgon of Ser. No. 48,38l, June 22, 1970, power circuit is converted into an alternating current an of prescribed frequency through a DC AC conversion r circuit. The alternating current flows through a battery [30] Foreign Appuufion by way of a DC blocking device and the voltage drop July 1, 1969 Japan 44/53589 due m the internal resistance of the battery is i duced into an AC voltmeter circuit. The internal resis- [52] Cl 324/29.5, 324/64, 340/249 m, f the battery is indicated at thc indicating pop Int. Cl. ,G0ln 27/46 tion of the AC voltmeter circuit so tha it is rectly.

7 Claims, 10 Drawing Figures A 5 a Y 0 l\ Eu 5 BLOCK/N6 b 3 2 051005 0k 9 Q QKD I F L1 9 y a BAT- m 1 e v p raw JM I A6 voumrm OIIMMETER FOR MEASURING TIIE INTERNAL RESISTANCE OF A BATTERY AND DIRECTLY READING THE MEASURED RESISTANCE VALUE This is a continuation, of application Ser. No. 48,381, filed June 22, 1970 and now abandoned.

The present invention relates to an ohmmeter for a battery.

The ohmmeter for a battery in accordance with the present invention is adapted to measure the internal resistance of a battery on the same principle as that of the standard for measurement brought forward by IEC (International Electrotechnical Commission).

As for the battery to be measured for internal resistance in the present invention, a storage battery can be measured as well as a dry battery such as a manganese dry cell, mercury battery and the like generally in use.

The primary object of the present invention is to provide an ohmmeter for a battery in which an alternating current flows through the battery and the voltage drop due to the internal resistance of the battery is introduced into an AC voltmeter circuit, thereby indicating the magnitude of the internal resistance of the battery so as to be directly read.

Another object of the present invention is to provide an ohmmeter for a battery in which the circuit construction is simplified so that the operation thereof may be conducted easily and it may be comfortably carried.

Still another object of the present invention is to provide an ohmmeter for a battery which is of use for checking and making uniform the quality of the batteries in the manufacturing process thereof.

Now the ohmmeter of the present invention will be described in comparison with the conventional type of ohmmeter of this kind in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic diagram of the circuit of the conventional ohmmeter,

FIG. 2 is a schematic diagram of the circuit of another conventional ohmmeter,

FIG. 3 is a schematic diagram of the circuit of still another conventional ohmmeter,

FIG. 4 is a diagram of the electrical circuit for explanation of the principle of the ohmmeter for a battery in accordance with the present invention,

' FIG. 5 is a block diagram of the ohmmeter is accordance with an embodiment of the present invention,

FIG. 6 is a view of the electrical circuit of the ohmmeter in accordance with the embodiment of the present invention shown in FIG. 5,

FIG. 7 is a block diagram of the ohmmeter in accordance with another embodiment of the present invention in which the DC power circuit in the ohmmeter shown in FIG. 6 is modified,

FIG. 8 is a block diagram of the ohmmeter in accordance with still another embodiment of the present invention in which the DC constant-voltage circuit in the ohmmeter shown in FIG. 6 is modified,

FIG. 9 is a block diagram of the ohmmeter in accordance with still another embodiment of the present invention in which the constant-current type DC AC conversion circuit in the ohmmeter shown in FIG. 6 is modified, and

FIG. 10 is a block diagram of the ohmmeter in accordance with a further embodiment of the present invention in which the AC voltmeter circuit in the ohmmeter shown in FIG. 6 is modified.

There are two methods of measuring the internal resistance of a battery, that is, AC method and DC method. In both methods, there are disadvantages in that the meter should be adjusted, the measured value should be calculated, or a precise measurement cannot be made, in the event that the conventional bridge method or voltmeter method is applied.

For instance, the Kohlrausch bridge method will be described as an example of the measurement by the AC method. In this method, the battery to be measured P is connected in one side of a bridge circuit as shown in FIG. I. The variable resistances R R are controlled to balance the circuit so that the current may not flow through the detector D in the circuit. The internal resistance R of the battery P is determined by the following balance formula in which the value of the variable resistances R and R is taken under balanced conditions. The condensers C, and C are blocking condensers for blocking the direct current from the battery P.

As an example of the measurement of the resistance of the battery by the DC method, Mances method will now be described. In this method, the battery to be measured P is connected in one side of a Wheatstone bridge circuit as shown in FIG. 2. The variable resistance R is controlled so that the galvanometer G may not be effected by the switching on and off of the switch K. Under the balanced condition, the internal resistance R of the battery P is determined by the following formula The voltmeter method will now be described hereinbelow. The battery P to be measured, a voltmeter V and a known resistor R are connected in the circuit as shown in FIG. 3. First, the voltage across the battery is measured with the switch K being opened. The measured voltage is indicated as Eo. Then, the voltage across the battery is measured with the switch K being closed. The measured voltage with the closed switch K is indicated as Vo. In the case that the internal resistance of the voltmeter is much larger than the internal resistance of the battery R and the resistance R, the internal resistance R of the battery is determined by the following formula:

It should be however noticed that the measurement of the voltage V0 across the battery with the closed switch K should be promptly conducted before the polarization of the battery commences.

As apparent from the above description regarding the prior art method of measuring the internal resistance of the battery, adjustment or calculation has been necessitated in the prior art.

The present invention overcomes the above defects of the prior art. The principle thereof will now be described hereinbelow. As shown in FIG. 4, a resistor R, a DC blocking condenser C and the battery B to be measured are connected in series across an AC power source P. The voltge drop by the internal resistance R X of the battery B is measured with a voltmeter V coupled in parallel with the battery B. The internal resistance R is determined by the following formula and the internal resistance R may be indicated by the voltmeter using a scale of resistance. Thus, the internal resistance R can be directly read on the meter.

Now the present invention will be described in detail with reference to some embodiments thereof. In FIG.

5 the principal arrangement of the embodiments is shown with a block diagram, in which the reference character A indicates a DC power source circuit, B indicates a DC constant voltage circuit, C indicates a constant current type DC AC conversion circuit, D a DC blocking device, E .an AC volt-meter circuit, F a battery to be meauured, G, H current terminals of the battery, and I and J indicate the voltage terminals of the battery to be measured.

In the above-described arrangement of the circuit,

' when an inconstant voltage provided by the'DC power source circuit A is supplied to the DC constant voltage circuit B, the voltage is controlled to be constant and put into the constant current type DC AC conversion circuit C as an input power. By means of this constant current type DC AC conversion circuit C, the direct current is converted into an alternating current (of sine wave form) having a prescribed frequency, and the alternating current flows through the battery connected between the current terminals G and H by way of the DC blocking device D. At this time, the voltage across the battery F measured between the voltage terminals I and J drops due to the internal resistance thereof. The voltage across the battery is put into the AC voltmeter circuit E of high input inpedance as the detection input. Accordingly, if the indicator of the voltmeter circuit E is provided with a resistance indicating scale, the indication of the pointer becomes the indication in ohms of the internal resistance of the battery.

Now an embodiment of the ohmmeter in accordance with the present invention will be described in detail referring to FIG. 6. In the embodiment, the DC power source circuit A includes batteries 1 so that the ohmmeter may be able to be used without a commercial AC power source. The DC constant voltage circuit B consists of a constant voltage diode 2, a transistor 4, a resistor 3, and a capacitor 5 connected as shown in FIG. 6, and automatically controls the voltage across the battery 1 by suppressing the fluctuation thereof to provide a stable constant voltage power source.

The constant current type DC AC conversion circuit C consists of a voltage controlling circuit C, and a push-pull type DC AC conversion circuit C, combined with the former. The voltage controlling circuit C, consists of a constant voltage diode 8, transistors 9 and 10, diodes 11 and 13, a current transformer 14, resistors 6 and 7, and a capacitor 12 connected as shown in FIG. 6. The push-pull type DC AC conversion circuit C consists of transistors 15 and 16, an oscillation transformer 18 and a resistor 17 connected as shown in the drawing. Through this DC AC conversion circuit C, a constant alternating current of a prescribed frequency, e.g., a sine wave of mA and 1,000 cycles, is applied to the battery F as a load. The AC voltmeter circuit E consists of an AC amplification circuit portion E and an indicating circuit portion E The AC amplification circuit portion E, is a CR coupling amplification circuit composed of a collector grounded circuit of high input impedance consisting of a transistor 22, resistors 20, 21 and 23, and capacitors 19 and 24 connected as shown in FIG. 6, and a high amplification transistor circuit consisting of a transistor 27 having an emitter grounded through the low AC im-.

pedance of capacitors 29 and 5 and resistors 25, 26, 28 and 30, connected as shown in the drawing. The constant DC voltage used for this circuit E, is obtained at the output terminals of the DC constant voltage circit B. When the constant alternating current flows through the battery F between the current terminals Gand H, the voltage drop due to the internal resistance of the battery can be detected at the voltage terminals I and J. The indicating circuit portion E, of the AC voltmeter circuit E consists of a semi-conductor rectifier 32 and a DC meter 33 connected as shown in FIG. 6, and rectifies the output current amplified by the AC amplification circuit E, so that the pointer in the DC meter 33 provided with a resistance scale indicates the internal resistance of the battery F. The DC blocking device D consisting of a non-polarization capacitor is connected in series between theconstant current type DC AC FIG. 6 is illustrated. In this modification, a DC power circuit A consisting of a commercial AC power source 34, a transformer 35 and a semiconductor rectifier36 is substituted for the DC power source circuit A so that the ohmmeter may be used for a long time with a commercial AC power source.

. In FIG. 8 a modification of the ohmmeter shown in FIG. 6 is illustrated with a block diagram, in which a DC constant voltage circuit B consisting of a constant voltage diode 37, transistors '39 and 42, resistors 38, 40 and 41, and'a capacitor 43 connected as shown in the drawing is substituted for the DC constant voltage circuit B.

In the DC constant voltage circuit B in the ohmmeter shown in FIG. 6, when the voltage across the emitter and base of the transistor 4 varies due to temperature variation, the output voltage is varied, which results in error in indication. In order to prevent the error in indication due to the temperature variation, another transistor 39 of a different type is connected with the transistor 42 so that the variation in voltage due to the temperature variation across the emitter and base of the respective transistors 39 and 42 may cancel each other. Thus, the output voltage is stabilized for the effect of the variation in temperature. The above stabilization can be simply explained by the following formulae (1) and (2). The relation between the output voltage E of the DC constant voltage circuit B,.the terminal voltage E of the constant voltage diode 2,-and the voltage E across the emitter and base of the transistor 4 is EL=E E I and the relation betweenthe outputE of the DC constant voltage circuit B, the terminalvoltage E, of

the constant voltage diode 37, the voltage E across the emitter and base of the transistor 42, and the voltage E across the emitter and base of the transistor 39 is Accordingly, if the transistors 39 and 42 are selected so that the relation E z E is satisfied, the formula (2) becomes E E which makes the output voltage be independent of the voltage across the emitter and base of the transistors.

Inthe circuit connetion of the DC constant voltage circuit B, the transistor 42 is connected in series between the DC power source A and the constant current type DC AC conversion circuit C. The collector of the transistor 42 is connected with the negative side of the DC power source A, the emitter thereof is connected with the constant current type DC AC conversion circuit C, and the base thereof is connected with the e'mitterof the transistor 39 and connected through a reslstor 4 1 with the negative side of the DC power source A. The baseof the transistor 39 is connected with the positive side of the DC power source A through a constant voltage diode 37 and connected with the negative side of the DC power source A through a resistor 38. The collector of the transistor 39 is connected with the positive side of the DC power source A through a resistor 40.

. In FIG. 9, another embodiment of the ohmmeter of the present invention is shown in which the ohmmeter shown in FIG. 6 is modified. The constant current type DC AC conversion circuit C in the ohmmeter shown in FIG. 6 is substituted for by a modified constant current type DC- AC conversion circuit C. The constant current type DC AC conversion circuit C consists of a voltage control circuit C, and a push-pull type DC- AC conversion circuit C The voltage control circuit C, consists of a control circuit consisting of a detecting transistor 44, acontrol transistor 46 and resistors 45 and 47, a voltage feedback circuit consisting of a rectifier 48 for rectifying the feedback voltage across the third coil 80 of the oscillation transformer 56 to put signals into the base of the control transistor 46, a resistor 57, a capacitor 49 and the third coil 80, and a current feedback circuit consisting of a rectifier 52 for rectifying the feedback current through the second coil 81 of the oscillation transformer 56 to put the signals into the base of the detection transistor 46, a resistor 50 and a capacitor 51. The push-pull type DC 4 AC conversion circuit C, consists of transistors 53 and 54, a collector coil 82, a base coil 83, the foregoing second and third coils 81 and 80, an oscillation transformer 56 and a resistor 55 connected as shown in FIG. 9. While in the constant current type DC AC conversion circuit C in the ohmmeter shown in FIG. 6 the input into the DC AC conversion circuit C, is controlled only by the current feedback to make the load current constant, in the constant current type DC AC conversion circuit C in the ohmmeter shown in FIG. 9 the input into the DC AC conversion circuit C, is controlled by both the voltage and current feedbacks to make the load current constant. Therefore, in the ohmmeter in accordance with the embodiment shown in FIG. 9, the efficiency of control is much improved and the synchronization can be easily conducted between the oscillation and the load current. Accordingly, a precise measurement can be accomplished in the case that a synchronous rectitier circuit is substituted for the rectifier 32 for converting the AC output from the AC amplification circuit portion E, into the direct current in the AC voltmeter E.

The constant current operation of the circuit C will now be described hereinbelow.

In the eventthat the load current isreduced, the volt age drop across the resistor 50 is reduced and the base potential of the detection transistor 44 is lowered. Accordingly, the collector current isreduced and the voltage drop across the resistor 45 is reduced, and the voltage across the base and emitter of the control transistor 46 is raised, which results in reduction in the voltage across the emitter and collector of the control transis- On the other hand, if the load current is reduced, the

output voltage is raised due to the lightload at the oscillation transformer 56. Then the voltage across the resistor 57 is raised and the DC voltage rectified through the rectifier 48 is also raised resulting in the rise of the voltage across the base and emitter of the control transistor 46. On account of the above, the voltage across the collector and emitter is lowered 'and the input voltage of the DC AC conversion circuit C, is raised. In response to the rising of the input voltage of the DC AC conversion circuit C the output voltage is raised and the output current (load current) is increased to return to its initial condition. In'the case that the load current is increased, entirely the reverse operation .is conducted.

In FIG. 10, another embodiment of the present invention is shown in which the AC amplification circuit E, in the AC voltmeter circuit'E of the ohmmeter embodiment shown in FIG. 6 is substituted for by an AC amplification circuit E, consisting of transistors 61 and 66, resistors 59,60, 62, 64, 65,67, 69 and 71, capacitors 58, 63, 68 and 70, and a resistance element 72 having a negative temperature coefficient. The AC amplification circuit E, corresponds to a circuit consisting of the AC amplification circuit E, and a negative feedback circuit E, connected between the emitter of the transistor 22 and the collector of the transistor 27 in the circuit E, (FIG. 6). In FIG. 10, the negative feedback circuit E, is connected between the emitter of the transistor 61 and the collector of the transistor 66. By the provision of the negative feedback circuit E, the temperature characteristic is improved. Since the coefficient of the temperature characteristic of the AC amplification circuit E, shown in FIG. 6 is positive, the negative feedback circuit E having a negative temperature coefficient is disposed between the emitter of the transistor 61 and the collector of the transistor 66 in the AC amplification circuit E, as shown in FIG. 10 in order to compensate the positive temperature variation. The negative feedback circuit E is composed of a thermistor 72 and a resistor 71 connected in series for providing a proper negative temperature coefficient.

In accordance with the present invention as described above, it is possible to read directly the internal resistance of a battery through a wide range and with high accuracy. Furthermore, the ohmmeter can be made into a compact portable size and it can be operated with a DC power source as well as an AC power source. The ohmmeter in accordance with the present invention is useful, as apparent from the above, for quality control in the battery manufacturing process.

What is claimed is:

1. An ohmmeter for measuring the internal resistance of a battery comprising a DC power source circuit;

a DC constant voltage circuit for producing a DC constant voltage output from the DC power of said DC power source circuit,

a DC-AC conversion circuit for converting said DC constant voltage output to an AC constant current having a relatively high frequency; said DC constant voltage circuit being a series-type constant voltage circuit comprising a control transistor having a collector connected to one output terminal of said DC power source circuit, an emitter connected to one input terminal of said DC-AC conversion circuit, and a base connected to said one output terminal of said DC power source circuit through a resistor; and a reference transistor having an emitter connected to the base of said control transistor and a base connected to the other output terminal of said DC power source circuit through a constant voltage diode and also to said one output terminal of said DC power source circuit through another resistor;

a DC blocking device, said AC constant current being applied to a battery to be measured through said DC blocking device, said DC blocking device preventing DC current from flowing from the battery; and i an AC voltmeter circuit including an indicator connected acrossthe battery for measuring the AC voltage drop of the battery due to its internal resistance, said indicator of said AC voltmeter circuit being adapted to indicate directly the internal resistance of the battery.

2. An ohmmeter for measuring the internal impedance of a battery according to claim 1 wherein said control transistor and reference transistor have the same temperature characteristic with respect to the voltage across the emitter and base thereof, and one of said transistors is of PNP type and the other of said transistor is of NPN type.

3. An ohmmeter for measuring the internal resistance of a battery comprising a DC power source circuit;

a DC constant voltage circuit for producing a DC constant voltage output from the DC power of said DC power source circuit;

a DC-AC conversion circuit for converting said DC constant voltage output to an AC output of a constant current having a sine wave of a predetermined frequency, said DC-AC conversion circuit including means for maintaining the current and voltage of said AC output at constant; and further comprising means for converting the DC voltage to an AC voltage, said converting means including an oscillation transformer having a secondary coil for producing said AC constant current and a control circuit connected in circuit between said DC constant voltage circuit and said converting means for controlling said DC constant voltage produced by said DC constant voltage circuit in accordance with a feed-back current and a feed-back voltage supplied 6 from said converting means thereby applying the controlled DC constant voltage to said converting means; current feed-back means including a first circuit connected between said secondary coil and the battery to be measured for taking out a current component relating to said AC constant current applied to said battery, and a rectifying circuit connected between said first circuit and said control circuit for producing said feed-back current by rectifying said current component; and voltage feedback means including a third coil of said oscillation transformer for taking out a voltage component proportional to a voltage induced to said secondary coil, and a rectifying circuit connected between said third coil and said control circuit for producing said feed-back voltage by rectifying said voltage component;

a DC blocking device, said AC constant current being applied to a battery to be measured through said DC blocking device, said DC blocking device preventing DC current from flowing from the battery; and

an AC voltmeter circuit including an indicator connected across the battery for measuring the AC voltage drop of the battery due to its internal resistance, said indicator of said AC voltmeter circuit being adapted to indicate directly the internal resistance of the battery.

4. An ohmmeter for measuring the internal resistance of a battery comprising: A DC power source circuit;

a DC constant voltage circuit including a first control transistor connected in series between said DC power source and a voltage control circuit for producing a DC constant voltage from the DC power of said DC power source circuit;

a DC-AC conversion circuit comprising said DC voltage control circuit and an oscillation circuit, said DC voltage control circuit including a second control transistor connected in series between said DC constant voltage circuit and said oscillation circuit for controlling said DC constant voltage thereby supplying said oscillation circuit with a DC controlled voltage, and said oscillation circuit including a pair of push-pull connected output transistors for converting said DC controlled voltage to an AC controlled voltage and a transformer having a primary'winding connected to said pair of output transistors and a secondary winding for producing an AC output voltage proportional to said AC controlled voltage;

connecting means for connecting said secondary winding to a battery to be measured, said means including a DC blocking device for preventing DC current from flowing from said connected battery and terminal means including current and voltage terminals for supplying said connected battery with a current from said output voltage of said secondary winding through said current terminals and takingout the voltage drop of said connected battery through said voltage terminals;

means for detecting variation of said current supplied to said battery through said connecting means and applying a signal relating to said variation to said second control transistor for controlling the same; and

indicator means comprising an AC amplifier connected to said voltage terminals for amplifying said voltage drop of said battery and an indicator circuit including a rectifier and an indicator connected to said amplifier through said rectifier for indicating directly the internal resistance of said battery by measuring said amplified voltage drop after rectification.

5. An ohmmeter according to claim 4, wherein said DC power source circuit includes a battery as a DC power source and said DC blocking device includes a non-polarized capacitor.

6. An ohmmeter according to claim 4, wherein said AC amplifier of said indicator means includes an input transistor having a collector connected to ground.

thereby providing a large input impedance, an output take out the voltage drop of said connected battery. i i

Claims (7)

1. An ohmmeter for measuring the internal resistance of a battery comprising a DC power source circuit; a DC constant voltage circuit for producing a DC constant voltage output from the DC power of said DC power source circuit, a DC-AC conversion circuit for converting said DC constant voltage output to an AC constant current having a relatively high frequency; said DC constant voltage circuit being a series-type constant voltage circuit comprising a control transistor having a collector connected to one output terminal of said DC power source circuit, an emitter connected to one input terminal of said DC-AC conversion circuit, and a base connected to said one output terminal of said DC power source circuit through a resistor; and a reference transistor having an emitter connected to the base of said control transistor and a base connected to the other output terminal of said DC power source circuit through a constant voltage diode and also to said one output terminal of said DC power source circuit through another resistor; a DC blocking device, said AC constant current being applied to a battery to be measured through said DC blocking device, said DC blocking device preventing DC current from flowing from the battery; and an AC voltmeter circuit including an indicatOr connected across the battery for measuring the AC voltage drop of the battery due to its internal resistance, said indicator of said AC voltmeter circuit being adapted to indicate directly the internal resistance of the battery.
2. An ohmmeter for measuring the internal impedance of a battery according to claim 1 wherein said control transistor and reference transistor have the same temperature characteristic with respect to the voltage across the emitter and base thereof, and one of said transistors is of PNP type and the other of said transistor is of NPN type.
3. An ohmmeter for measuring the internal resistance of a battery comprising a DC power source circuit; a DC constant voltage circuit for producing a DC constant voltage output from the DC power of said DC power source circuit; a DC-AC conversion circuit for converting said DC constant voltage output to an AC output of a constant current having a sine wave of a predetermined frequency, said DC-AC conversion circuit including means for maintaining the current and voltage of said AC output at constant; and further comprising means for converting the DC voltage to an AC voltage, said converting means including an oscillation transformer having a secondary coil for producing said AC constant current and a control circuit connected in circuit between said DC constant voltage circuit and said converting means for controlling said DC constant voltage produced by said DC constant voltage circuit in accordance with a feed-back current and a feed-back voltage supplied from said converting means thereby applying the controlled DC constant voltage to said converting means; current feed-back means including a first circuit connected between said secondary coil and the battery to be measured for taking out a current component relating to said AC constant current applied to said battery, and a rectifying circuit connected between said first circuit and said control circuit for producing said feed-back current by rectifying said current component; and voltage feed-back means including a third coil of said oscillation transformer for taking out a voltage component proportional to a voltage induced to said secondary coil, and a rectifying circuit connected between said third coil and said control circuit for producing said feed-back voltage by rectifying said voltage component; a DC blocking device, said AC constant current being applied to a battery to be measured through said DC blocking device, said DC blocking device preventing DC current from flowing from the battery; and an AC voltmeter circuit including an indicator connected across the battery for measuring the AC voltage drop of the battery due to its internal resistance, said indicator of said AC voltmeter circuit being adapted to indicate directly the internal resistance of the battery.
4. An ohmmeter for measuring the internal resistance of a battery comprising: A DC power source circuit; a DC constant voltage circuit including a first control transistor connected in series between said DC power source and a voltage control circuit for producing a DC constant voltage from the DC power of said DC power source circuit; a DC-AC conversion circuit comprising said DC voltage control circuit and an oscillation circuit, said DC voltage control circuit including a second control transistor connected in series between said DC constant voltage circuit and said oscillation circuit for controlling said DC constant voltage thereby supplying said oscillation circuit with a DC controlled voltage, and said oscillation circuit including a pair of push-pull connected output transistors for converting said DC controlled voltage to an AC controlled voltage and a transformer having a primary winding connected to said pair of output transistors and a secondary winding for producing an AC output voltage proportional to said AC controlled voltage; connecTing means for connecting said secondary winding to a battery to be measured, said means including a DC blocking device for preventing DC current from flowing from said connected battery and terminal means including current and voltage terminals for supplying said connected battery with a current from said output voltage of said secondary winding through said current terminals and takingout the voltage drop of said connected battery through said voltage terminals; means for detecting variation of said current supplied to said battery through said connecting means and applying a signal relating to said variation to said second control transistor for controlling the same; and indicator means comprising an AC amplifier connected to said voltage terminals for amplifying said voltage drop of said battery and an indicator circuit including a rectifier and an indicator connected to said amplifier through said rectifier for indicating directly the internal resistance of said battery by measuring said amplified voltage drop after rectification.
5. An ohmmeter according to claim 4, wherein said DC power source circuit includes a battery as a DC power source and said DC blocking device includes a non-polarized capacitor.
6. An ohmmeter according to claim 4, wherein said AC amplifier of said indicator means includes an input transistor having a collector connected to ground thereby providing a large input impedance, an output transistor having an emitter connected to ground through a low AC impedance thereby providing a high amplification factor and negative feedback means including a resistance element having a negative temperature coefficient for connecting the collector of said output transistor to the emitter of said input transistor.
7. An ohmmeter accordingto claim 4, wherein said terminal means includes a pair of said current terminals adapted to be connected across said battery to be measured and a pair of said voltage terminals adapted to take out the voltage drop of said connected battery.
US3753094A 1969-07-01 1972-07-24 Ohmmeter for measuring the internal resistance of a battery and directly reading the measured resistance value Expired - Lifetime US3753094A (en)

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Cited By (148)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3873911A (en) * 1971-09-14 1975-03-25 Keith S Champlin Electronic battery testing device
US3909708A (en) * 1974-01-02 1975-09-30 Keith S Champlin Electronic battery testing device
US3969667A (en) * 1972-08-23 1976-07-13 The United States Of America As Represented By The Secretary Of The Navy Device for determining the state of charge in batteries
US4193025A (en) * 1977-12-23 1980-03-11 Globe-Union, Inc. Automatic battery analyzer
US4207611A (en) * 1978-12-18 1980-06-10 Ford Motor Company Apparatus and method for calibrated testing of a vehicle electrical system
US4207610A (en) * 1978-12-18 1980-06-10 Ford Motor Company Apparatus and method for testing and controlling manufacture of a vehicle electrical system
WO1983002005A1 (en) * 1981-12-04 1983-06-09 Bear Automative Service Equipm Automotive battery test apparatus
US4697134A (en) * 1986-07-31 1987-09-29 Commonwealth Edison Company Apparatus and method for measuring battery condition
US4719428A (en) * 1985-06-04 1988-01-12 Tif Instruments, Inc. Storage battery condition tester utilizing low load current
US5159272A (en) * 1988-07-27 1992-10-27 Gnb Incorporated Monitoring device for electric storage battery and configuration therefor
US5248934A (en) * 1992-01-10 1993-09-28 Roveti Denes K Method and apparatus for converting a conventional DC multimeter to an AC impedance meter
WO1993025917A1 (en) * 1992-06-12 1993-12-23 Emerson Electric Uk Limited A method and apparatus for battery testing
US5381096A (en) * 1992-04-09 1995-01-10 Hirzel; Edgar A. Method and apparatus for measuring the state-of-charge of a battery system
US5661463A (en) * 1995-04-17 1997-08-26 Communications Test Design, Inc. D.C. battery plant alarm monitoring remote apparatus
US6002238A (en) * 1998-09-11 1999-12-14 Champlin; Keith S. Method and apparatus for measuring complex impedance of cells and batteries
US6037777A (en) * 1998-09-11 2000-03-14 Champlin; Keith S. Method and apparatus for determining battery properties from complex impedance/admittance
US6037778A (en) * 1997-11-05 2000-03-14 Stat Engineering Company, L.L.C. Electronic battery testing device and method for testing batteries
US6081098A (en) * 1997-11-03 2000-06-27 Midtronics, Inc. Method and apparatus for charging a battery
US6091245A (en) * 1996-07-29 2000-07-18 Midtronics, Inc. Method and apparatus for auditing a battery test
US6137269A (en) * 1999-09-01 2000-10-24 Champlin; Keith S. Method and apparatus for electronically evaluating the internal temperature of an electrochemical cell or battery
US6163156A (en) * 1999-11-01 2000-12-19 Midtronics, Inc. Electrical connection for electronic battery tester
US6172505B1 (en) 1998-04-27 2001-01-09 Midtronics, Inc. Electronic battery tester
US6222370B1 (en) 1998-03-13 2001-04-24 Brian Walter Schousek Universal battery monitor
US6225808B1 (en) 2000-02-25 2001-05-01 Midtronics, Inc. Test counter for electronic battery tester
US6249124B1 (en) 1999-11-01 2001-06-19 Midtronics, Inc. Electronic battery tester with internal battery
US6262563B1 (en) 1998-09-11 2001-07-17 Keith S. Champlin Method and apparatus for measuring complex admittance of cells and batteries
US6294896B1 (en) 1998-09-11 2001-09-25 Keith S. Champlin Method and apparatus for measuring complex self-immitance of a general electrical element
US6304087B1 (en) 2000-09-05 2001-10-16 Midtronics, Inc. Apparatus for calibrating electronic battery tester
US6310481B2 (en) 1997-01-13 2001-10-30 Midtronics, Inc. Electronic battery tester
US6313607B1 (en) 1999-09-01 2001-11-06 Keith S. Champlin Method and apparatus for evaluating stored charge in an electrochemical cell or battery
US6316914B1 (en) 1999-05-05 2001-11-13 Midtronics, Inc. Testing parallel strings of storage batteries
US6323650B1 (en) 1999-04-08 2001-11-27 Midtronics, Inc. Electronic battery tester
US6329793B1 (en) 1996-07-29 2001-12-11 Midtronics, Inc. Method and apparatus for charging a battery
US6332113B1 (en) 1996-10-07 2001-12-18 Midtronics, Inc. Electronic battery tester
US6331762B1 (en) 1997-11-03 2001-12-18 Midtronics, Inc. Energy management system for automotive vehicle
US6351102B1 (en) 1999-04-16 2002-02-26 Midtronics, Inc. Automotive battery charging system tester
US6359441B1 (en) 1999-04-30 2002-03-19 Midtronics, Inc. Electronic battery tester
US6363303B1 (en) 1999-11-01 2002-03-26 Midtronics, Inc. Alternator diagnostic system
US6384608B1 (en) 2001-03-13 2002-05-07 Actron Manufacturing Co. Battery tester using internal resistance to measure a condition of a battery
US6388448B1 (en) 2001-03-13 2002-05-14 Actron Manufacturing Co. Electronic battery tester with normal/cold test modes and terminal connection detection
US6417669B1 (en) 2001-06-11 2002-07-09 Keith S. Champlin Suppressing interference in AC measurements of cells, batteries and other electrical elements
US6424158B2 (en) 1998-07-27 2002-07-23 Midtronics, Inc. Apparatus and method for carrying out diagnostic tests on batteries and for rapidly charging batteries
US6441585B1 (en) 1999-06-16 2002-08-27 Midtronics, Inc. Apparatus and method for testing rechargeable energy storage batteries
US6445158B1 (en) 1996-07-29 2002-09-03 Midtronics, Inc. Vehicle electrical system tester with encoded output
US6456045B1 (en) 1999-04-16 2002-09-24 Midtronics, Inc. Integrated conductance and load test based electronic battery tester
US6466026B1 (en) 2001-10-12 2002-10-15 Keith S. Champlin Programmable current exciter for measuring AC immittance of cells and batteries
US6466025B1 (en) 2000-01-13 2002-10-15 Midtronics, Inc. Alternator tester
US6469511B1 (en) 2001-07-18 2002-10-22 Midtronics, Inc. Battery clamp with embedded environment sensor
US6519539B1 (en) 2000-09-29 2003-02-11 Hydrogenics Corporation Measurement of fuel cell impedance
US6544078B2 (en) 2001-07-18 2003-04-08 Midtronics, Inc. Battery clamp with integrated current sensor
US6566883B1 (en) 1999-11-01 2003-05-20 Midtronics, Inc. Electronic battery tester
US6586941B2 (en) 2000-03-27 2003-07-01 Midtronics, Inc. Battery tester with databus
US20030184306A1 (en) * 2002-03-29 2003-10-02 Bertness Kevin I. Battery tester with battery replacement output
US6633165B2 (en) 1997-11-03 2003-10-14 Midtronics, Inc. In-vehicle battery monitor
US6696819B2 (en) 2002-01-08 2004-02-24 Midtronics, Inc. Battery charge control device
US20040046564A1 (en) * 2002-09-05 2004-03-11 Klang James K. Battery test outputs adjusted based upon battery temperature and the state of discharge of the battery
US20040091759A1 (en) * 2002-05-17 2004-05-13 Harrington David Athol Methods and apparatus for indicating a fault condition in fuel cells and fuel cell components
US6737831B2 (en) 1999-09-01 2004-05-18 Keith S. Champlin Method and apparatus using a circuit model to evaluate cell/battery parameters
US6759849B2 (en) 2000-03-27 2004-07-06 Kevin I. Bertness Battery tester configured to receive a removable digital module
US20040150405A1 (en) * 2002-12-03 2004-08-05 Stephen Burany Method and apparatus for monitoring fuel cell voltages
US6781382B2 (en) 2002-12-05 2004-08-24 Midtronics, Inc. Electronic battery tester
US6788025B2 (en) 2001-06-22 2004-09-07 Midtronics, Inc. Battery charger with booster pack
US6795782B2 (en) 1999-04-08 2004-09-21 Midtronics, Inc. Battery test module
US20040220752A1 (en) * 2003-02-04 2004-11-04 Hydrogenics Corporation System and method for measuring internal resistance of electrochemical devices
US6816797B2 (en) 2000-09-29 2004-11-09 Hydrogenics Corporation System and method for measuring fuel cell voltage and high frequency resistance
US20040251907A1 (en) * 2003-06-11 2004-12-16 Kalley Terrence D. Part tester and method
US6850037B2 (en) 1997-11-03 2005-02-01 Midtronics, Inc. In-vehicle battery monitor
US20050035752A1 (en) * 1996-07-29 2005-02-17 Bertness Kevin I. Alternator tester
US20050057256A1 (en) * 2000-03-27 2005-03-17 Midtronics, Inc. Scan tool for electronic battery tester
US6871151B2 (en) 1997-11-03 2005-03-22 Midtronics, Inc. Electronic battery tester with network communication
US20050077904A1 (en) * 2003-10-08 2005-04-14 Midtronics, Inc. Electronic battery tester with probe light
US6885195B2 (en) 1996-07-29 2005-04-26 Midtronics, Inc. Method and apparatus for auditing a battery test
US6888468B2 (en) 2003-01-22 2005-05-03 Midtronics, Inc. Apparatus and method for protecting a battery from overdischarge
US6891378B2 (en) 2003-03-25 2005-05-10 Midtronics, Inc. Electronic battery tester
US6906523B2 (en) 2000-09-14 2005-06-14 Midtronics, Inc. Method and apparatus for testing cells and batteries embedded in series/parallel systems
US6913483B2 (en) 2003-06-23 2005-07-05 Midtronics, Inc. Cable for electronic battery tester
US6914413B2 (en) 1996-07-29 2005-07-05 Midtronics, Inc. Alternator tester with encoded output
US6919725B2 (en) 2003-10-03 2005-07-19 Midtronics, Inc. Electronic battery tester/charger with integrated battery cell temperature measurement device
US6930485B2 (en) 2002-03-14 2005-08-16 Midtronics, Inc. Electronic battery tester with battery failure temperature determination
US6941234B2 (en) 2001-10-17 2005-09-06 Midtronics, Inc. Query based electronic battery tester
US6967484B2 (en) 2000-03-27 2005-11-22 Midtronics, Inc. Electronic battery tester with automotive scan tool communication
US7003410B2 (en) 1996-07-29 2006-02-21 Midtronics, Inc. Electronic battery tester with relative test output
US7012433B2 (en) 2002-09-18 2006-03-14 Midtronics, Inc. Battery tester upgrade using software key
US7015674B2 (en) 2001-06-22 2006-03-21 Midtronics, Inc. Booster pack with storage capacitor
US7039533B2 (en) 1999-04-08 2006-05-02 Midtronics, Inc. Battery test module
US7058525B2 (en) 1999-04-08 2006-06-06 Midtronics, Inc. Battery test module
US20060125482A1 (en) * 2004-12-09 2006-06-15 Midtronics, Inc. Apparatus and method for predicting battery capacity and fitness for service from a battery dynamic parameter and a recovery voltage differential
US7106070B2 (en) 2004-07-22 2006-09-12 Midtronics, Inc. Broad-band low-inductance cables for making Kelvin connections to electrochemical cells and batteries
US7116109B2 (en) 2003-11-11 2006-10-03 Midtronics, Inc. Apparatus and method for simulating a battery tester with a fixed resistance load
US7119686B2 (en) 2004-04-13 2006-10-10 Midtronics, Inc. Theft prevention device for automotive vehicle service centers
US7126341B2 (en) 1997-11-03 2006-10-24 Midtronics, Inc. Automotive vehicle electrical system diagnostic device
US7154276B2 (en) 2003-09-05 2006-12-26 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US20070069734A1 (en) * 1997-11-03 2007-03-29 Bertness Kevin I Automotive vehicle electrical system diagnostic device
US7198510B2 (en) 2001-11-14 2007-04-03 Midtronics, Inc. Kelvin connector for a battery post
US7208914B2 (en) 2002-12-31 2007-04-24 Midtronics, Inc. Apparatus and method for predicting the remaining discharge time of a battery
US20070259256A1 (en) * 2004-11-29 2007-11-08 Jean-Marc Le Canut Systems and methods for detecting and indicating fault conditions in electrochemical cells
US7319304B2 (en) 2003-07-25 2008-01-15 Midtronics, Inc. Shunt connection to a PCB of an energy management system employed in an automotive vehicle
US7398176B2 (en) 2000-03-27 2008-07-08 Midtronics, Inc. Battery testers with secondary functionality
US7408358B2 (en) 2003-06-16 2008-08-05 Midtronics, Inc. Electronic battery tester having a user interface to configure a printer
US20080252437A1 (en) * 2007-04-16 2008-10-16 Midtronics, Inc. Battery run down indicator
US7479763B2 (en) 2001-06-22 2009-01-20 Midtronics, Inc. Apparatus and method for counteracting self discharge in a storage battery
US7498767B2 (en) 2005-02-16 2009-03-03 Midtronics, Inc. Centralized data storage of condition of a storage battery at its point of sale
US7501795B2 (en) 2001-06-22 2009-03-10 Midtronics Inc. Battery charger with booster pack
US7505856B2 (en) 1999-04-08 2009-03-17 Midtronics, Inc. Battery test module
US20090192726A1 (en) * 2008-01-25 2009-07-30 Eveready Battery Company, Inc. Electrochemical Composition Detection Device and Method Thereof
US7595643B2 (en) 2003-11-11 2009-09-29 Midtronics, Inc. Apparatus and method for simulating a battery tester with a fixed resistance load
US7598699B2 (en) 2004-02-20 2009-10-06 Midtronics, Inc. Replaceable clamp for electronic battery tester
US7598744B2 (en) 2000-03-27 2009-10-06 Midtronics, Inc. Scan tool for electronic battery tester
US7598743B2 (en) 2000-03-27 2009-10-06 Midtronics, Inc. Battery maintenance device having databus connection
US7642786B2 (en) 2004-06-01 2010-01-05 Midtronics, Inc. Battery tester capable of identifying faulty battery post adapters
US7688074B2 (en) 1997-11-03 2010-03-30 Midtronics, Inc. Energy management system for automotive vehicle
US7706991B2 (en) 1996-07-29 2010-04-27 Midtronics, Inc. Alternator tester
US7710119B2 (en) 2004-12-09 2010-05-04 Midtronics, Inc. Battery tester that calculates its own reference values
US7723993B2 (en) 2002-09-05 2010-05-25 Midtronics, Inc. Electronic battery tester configured to predict a load test result based on open circuit voltage, temperature, cranking size rating, and a dynamic parameter
US7772850B2 (en) 2004-07-12 2010-08-10 Midtronics, Inc. Wireless battery tester with information encryption means
US7774151B2 (en) 1997-11-03 2010-08-10 Midtronics, Inc. Wireless battery monitor
US7777612B2 (en) 2004-04-13 2010-08-17 Midtronics, Inc. Theft prevention device for automotive vehicle service centers
US7791348B2 (en) 2007-02-27 2010-09-07 Midtronics, Inc. Battery tester with promotion feature to promote use of the battery tester by providing the user with codes having redeemable value
US7977914B2 (en) 2003-10-08 2011-07-12 Midtronics, Inc. Battery maintenance tool with probe light
US8164343B2 (en) 2003-09-05 2012-04-24 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US8198900B2 (en) 1996-07-29 2012-06-12 Midtronics, Inc. Automotive battery charging system tester
US8203345B2 (en) 2007-12-06 2012-06-19 Midtronics, Inc. Storage battery and battery tester
US8306690B2 (en) 2007-07-17 2012-11-06 Midtronics, Inc. Battery tester for electric vehicle
US8344685B2 (en) 2004-08-20 2013-01-01 Midtronics, Inc. System for automatically gathering battery information
US8436619B2 (en) 2004-08-20 2013-05-07 Midtronics, Inc. Integrated tag reader and environment sensor
US8442877B2 (en) 2004-08-20 2013-05-14 Midtronics, Inc. Simplification of inventory management
US8513949B2 (en) 2000-03-27 2013-08-20 Midtronics, Inc. Electronic battery tester or charger with databus connection
US20130249575A1 (en) * 2012-03-22 2013-09-26 Continental Automotive Gmbh Device and method for measuring a value of a resistor
US8738309B2 (en) 2010-09-30 2014-05-27 Midtronics, Inc. Battery pack maintenance for electric vehicles
RU2531062C1 (en) * 2013-03-26 2014-10-20 Открытое акционерное общество "Научно-производственное объединение измерительной техники" Device of accumulator battery control
US8872517B2 (en) 1996-07-29 2014-10-28 Midtronics, Inc. Electronic battery tester with battery age input
RU2536780C1 (en) * 2010-12-10 2014-12-27 Ниссан Мотор Ко., Лтд. Device and method to measure inner resistance for packaged battery
US8958998B2 (en) 1997-11-03 2015-02-17 Midtronics, Inc. Electronic battery tester with network communication
US9018958B2 (en) 2003-09-05 2015-04-28 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US9201120B2 (en) 2010-08-12 2015-12-01 Midtronics, Inc. Electronic battery tester for testing storage battery
US9229062B2 (en) 2010-05-27 2016-01-05 Midtronics, Inc. Electronic storage battery diagnostic system
US20160020618A1 (en) * 2014-07-21 2016-01-21 Ford Global Technologies, Llc Fast Charge Algorithms for Lithium-Ion Batteries
US9244100B2 (en) 2013-03-15 2016-01-26 Midtronics, Inc. Current clamp with jaw closure detection
US9255955B2 (en) 2003-09-05 2016-02-09 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US9274157B2 (en) 2007-07-17 2016-03-01 Midtronics, Inc. Battery tester for electric vehicle
US9312575B2 (en) 2013-05-16 2016-04-12 Midtronics, Inc. Battery testing system and method
WO2016071213A1 (en) * 2014-11-03 2016-05-12 Bayerische Motoren Werke Aktiengesellschaft Circuit arrangement and method for determining the impedance of a test battery
US9419311B2 (en) 2010-06-18 2016-08-16 Midtronics, Inc. Battery maintenance device with thermal buffer
US9425487B2 (en) 2010-03-03 2016-08-23 Midtronics, Inc. Monitor for front terminal batteries
US9496720B2 (en) 2004-08-20 2016-11-15 Midtronics, Inc. System for automatically gathering battery information
US9588185B2 (en) 2010-02-25 2017-03-07 Keith S. Champlin Method and apparatus for detecting cell deterioration in an electrochemical cell or battery
US9851411B2 (en) 2012-06-28 2017-12-26 Keith S. Champlin Suppressing HF cable oscillations during dynamic measurements of cells and batteries
US9923289B2 (en) 2014-01-16 2018-03-20 Midtronics, Inc. Battery clamp with endoskeleton design

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE901080C (en) * 1951-08-03 1954-01-07 Licentia Gmbh An arrangement for measuring the internal resistance of galvanic elements or cells and accumulators
US2871446A (en) * 1955-01-28 1959-01-27 Continental Oil Co Wide-range resistance and resistivity measuring apparatus
US2896159A (en) * 1955-07-14 1959-07-21 Webster Instr Inc Method and apparatus for measuring electrical resistance

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE901080C (en) * 1951-08-03 1954-01-07 Licentia Gmbh An arrangement for measuring the internal resistance of galvanic elements or cells and accumulators
US2871446A (en) * 1955-01-28 1959-01-27 Continental Oil Co Wide-range resistance and resistivity measuring apparatus
US2896159A (en) * 1955-07-14 1959-07-21 Webster Instr Inc Method and apparatus for measuring electrical resistance

Cited By (203)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3873911A (en) * 1971-09-14 1975-03-25 Keith S Champlin Electronic battery testing device
US3969667A (en) * 1972-08-23 1976-07-13 The United States Of America As Represented By The Secretary Of The Navy Device for determining the state of charge in batteries
US3909708A (en) * 1974-01-02 1975-09-30 Keith S Champlin Electronic battery testing device
US4193025A (en) * 1977-12-23 1980-03-11 Globe-Union, Inc. Automatic battery analyzer
US4207611A (en) * 1978-12-18 1980-06-10 Ford Motor Company Apparatus and method for calibrated testing of a vehicle electrical system
US4207610A (en) * 1978-12-18 1980-06-10 Ford Motor Company Apparatus and method for testing and controlling manufacture of a vehicle electrical system
WO1983002005A1 (en) * 1981-12-04 1983-06-09 Bear Automative Service Equipm Automotive battery test apparatus
US4423378A (en) * 1981-12-04 1983-12-27 Bear Automotive Service Equipment Company Automotive battery test apparatus
US4719428A (en) * 1985-06-04 1988-01-12 Tif Instruments, Inc. Storage battery condition tester utilizing low load current
WO1988001055A1 (en) * 1986-07-31 1988-02-11 Commonwealth Edison Company Apparatus and method for measuring battery condition
US4697134A (en) * 1986-07-31 1987-09-29 Commonwealth Edison Company Apparatus and method for measuring battery condition
US5159272A (en) * 1988-07-27 1992-10-27 Gnb Incorporated Monitoring device for electric storage battery and configuration therefor
US5248934A (en) * 1992-01-10 1993-09-28 Roveti Denes K Method and apparatus for converting a conventional DC multimeter to an AC impedance meter
US5381096A (en) * 1992-04-09 1995-01-10 Hirzel; Edgar A. Method and apparatus for measuring the state-of-charge of a battery system
WO1993025917A1 (en) * 1992-06-12 1993-12-23 Emerson Electric Uk Limited A method and apparatus for battery testing
GB2269019A (en) * 1992-06-12 1994-01-26 Emerson Electric Uk Ltd Testing batteries
GB2269019B (en) * 1992-06-12 1996-02-14 Emerson Electric Uk Ltd A method and apparatus for battery testing
US5661463A (en) * 1995-04-17 1997-08-26 Communications Test Design, Inc. D.C. battery plant alarm monitoring remote apparatus
US7295936B2 (en) 1996-07-29 2007-11-13 Midtronics, Inc. Electronic battery tester with relative test output
US8198900B2 (en) 1996-07-29 2012-06-12 Midtronics, Inc. Automotive battery charging system tester
US6445158B1 (en) 1996-07-29 2002-09-03 Midtronics, Inc. Vehicle electrical system tester with encoded output
US8872517B2 (en) 1996-07-29 2014-10-28 Midtronics, Inc. Electronic battery tester with battery age input
US6091245A (en) * 1996-07-29 2000-07-18 Midtronics, Inc. Method and apparatus for auditing a battery test
US6885195B2 (en) 1996-07-29 2005-04-26 Midtronics, Inc. Method and apparatus for auditing a battery test
US6914413B2 (en) 1996-07-29 2005-07-05 Midtronics, Inc. Alternator tester with encoded output
US7940052B2 (en) 1996-07-29 2011-05-10 Midtronics, Inc. Electronic battery test based upon battery requirements
US20050035752A1 (en) * 1996-07-29 2005-02-17 Bertness Kevin I. Alternator tester
US7246015B2 (en) 1996-07-29 2007-07-17 Midtronics, Inc. Alternator tester
US7656162B2 (en) 1996-07-29 2010-02-02 Midtronics Inc. Electronic battery tester with vehicle type input
US7706991B2 (en) 1996-07-29 2010-04-27 Midtronics, Inc. Alternator tester
US7003410B2 (en) 1996-07-29 2006-02-21 Midtronics, Inc. Electronic battery tester with relative test output
US6329793B1 (en) 1996-07-29 2001-12-11 Midtronics, Inc. Method and apparatus for charging a battery
US6332113B1 (en) 1996-10-07 2001-12-18 Midtronics, Inc. Electronic battery tester
US6392414B2 (en) 1997-01-13 2002-05-21 Midtronics, Inc. Electronic battery tester
US6310481B2 (en) 1997-01-13 2001-10-30 Midtronics, Inc. Electronic battery tester
US6633165B2 (en) 1997-11-03 2003-10-14 Midtronics, Inc. In-vehicle battery monitor
US20070069734A1 (en) * 1997-11-03 2007-03-29 Bertness Kevin I Automotive vehicle electrical system diagnostic device
US8674654B2 (en) 1997-11-03 2014-03-18 Midtronics, Inc. In-vehicle battery monitor
US6313608B1 (en) 1997-11-03 2001-11-06 Midtronics, Inc. Method and apparatus for charging a battery
US6850037B2 (en) 1997-11-03 2005-02-01 Midtronics, Inc. In-vehicle battery monitor
US7688074B2 (en) 1997-11-03 2010-03-30 Midtronics, Inc. Energy management system for automotive vehicle
US7774151B2 (en) 1997-11-03 2010-08-10 Midtronics, Inc. Wireless battery monitor
US7126341B2 (en) 1997-11-03 2006-10-24 Midtronics, Inc. Automotive vehicle electrical system diagnostic device
US8493022B2 (en) 1997-11-03 2013-07-23 Midtronics, Inc. Automotive vehicle electrical system diagnostic device
US6909287B2 (en) 1997-11-03 2005-06-21 Midtronics, Inc. Energy management system for automotive vehicle
US7003411B2 (en) 1997-11-03 2006-02-21 Midtronics, Inc. Electronic battery tester with network communication
US6104167A (en) * 1997-11-03 2000-08-15 Midtronics, Inc. Method and apparatus for charging a battery
US8958998B2 (en) 1997-11-03 2015-02-17 Midtronics, Inc. Electronic battery tester with network communication
US6081098A (en) * 1997-11-03 2000-06-27 Midtronics, Inc. Method and apparatus for charging a battery
US7999505B2 (en) 1997-11-03 2011-08-16 Midtronics, Inc. In-vehicle battery monitor
US7642787B2 (en) 1997-11-03 2010-01-05 Midtronics Inc. Automotive vehicle electrical system diagnostic device
US7705602B2 (en) 1997-11-03 2010-04-27 Midtronics, Inc. Automotive vehicle electrical system diagnostic device
US6331762B1 (en) 1997-11-03 2001-12-18 Midtronics, Inc. Energy management system for automotive vehicle
US6871151B2 (en) 1997-11-03 2005-03-22 Midtronics, Inc. Electronic battery tester with network communication
US6037778A (en) * 1997-11-05 2000-03-14 Stat Engineering Company, L.L.C. Electronic battery testing device and method for testing batteries
US6222370B1 (en) 1998-03-13 2001-04-24 Brian Walter Schousek Universal battery monitor
US6172505B1 (en) 1998-04-27 2001-01-09 Midtronics, Inc. Electronic battery tester
US6424158B2 (en) 1998-07-27 2002-07-23 Midtronics, Inc. Apparatus and method for carrying out diagnostic tests on batteries and for rapidly charging batteries
US6172483B1 (en) * 1998-09-11 2001-01-09 Keith S. Champlin Method and apparatus for measuring complex impedance of cells and batteries
US6002238A (en) * 1998-09-11 1999-12-14 Champlin; Keith S. Method and apparatus for measuring complex impedance of cells and batteries
US6294896B1 (en) 1998-09-11 2001-09-25 Keith S. Champlin Method and apparatus for measuring complex self-immitance of a general electrical element
US6037777A (en) * 1998-09-11 2000-03-14 Champlin; Keith S. Method and apparatus for determining battery properties from complex impedance/admittance
US6262563B1 (en) 1998-09-11 2001-07-17 Keith S. Champlin Method and apparatus for measuring complex admittance of cells and batteries
US6222369B1 (en) 1998-09-11 2001-04-24 Keith S. Champlin Method and apparatus for determining battery properties from complex impedance/admittance
US6707303B2 (en) 1999-04-08 2004-03-16 Midtronics, Inc. Electronic battery tester
US7039533B2 (en) 1999-04-08 2006-05-02 Midtronics, Inc. Battery test module
US6795782B2 (en) 1999-04-08 2004-09-21 Midtronics, Inc. Battery test module
US7058525B2 (en) 1999-04-08 2006-06-06 Midtronics, Inc. Battery test module
US6323650B1 (en) 1999-04-08 2001-11-27 Midtronics, Inc. Electronic battery tester
US6806716B2 (en) 1999-04-08 2004-10-19 Kevin I. Bertness Electronic battery tester
US7505856B2 (en) 1999-04-08 2009-03-17 Midtronics, Inc. Battery test module
US6456045B1 (en) 1999-04-16 2002-09-24 Midtronics, Inc. Integrated conductance and load test based electronic battery tester
US6351102B1 (en) 1999-04-16 2002-02-26 Midtronics, Inc. Automotive battery charging system tester
US6359441B1 (en) 1999-04-30 2002-03-19 Midtronics, Inc. Electronic battery tester
US6556019B2 (en) 1999-04-30 2003-04-29 Midtronics, Inc. Electronic battery tester
US6316914B1 (en) 1999-05-05 2001-11-13 Midtronics, Inc. Testing parallel strings of storage batteries
US6441585B1 (en) 1999-06-16 2002-08-27 Midtronics, Inc. Apparatus and method for testing rechargeable energy storage batteries
US6294897B1 (en) 1999-09-01 2001-09-25 Keith S. Champlin Method and apparatus for electronically evaluating the internal temperature of an electrochemical cell or battery
US6137269A (en) * 1999-09-01 2000-10-24 Champlin; Keith S. Method and apparatus for electronically evaluating the internal temperature of an electrochemical cell or battery
US6495990B2 (en) 1999-09-01 2002-12-17 Keith S. Champlin Method and apparatus for evaluating stored charge in an electrochemical cell or battery
US6313607B1 (en) 1999-09-01 2001-11-06 Keith S. Champlin Method and apparatus for evaluating stored charge in an electrochemical cell or battery
US6737831B2 (en) 1999-09-01 2004-05-18 Keith S. Champlin Method and apparatus using a circuit model to evaluate cell/battery parameters
US7557586B1 (en) 1999-11-01 2009-07-07 Midtronics, Inc. Electronic battery tester
US8754653B2 (en) 1999-11-01 2014-06-17 Midtronics, Inc. Electronic battery tester
US6163156A (en) * 1999-11-01 2000-12-19 Midtronics, Inc. Electrical connection for electronic battery tester
US6249124B1 (en) 1999-11-01 2001-06-19 Midtronics, Inc. Electronic battery tester with internal battery
US6363303B1 (en) 1999-11-01 2002-03-26 Midtronics, Inc. Alternator diagnostic system
US6566883B1 (en) 1999-11-01 2003-05-20 Midtronics, Inc. Electronic battery tester
US6466025B1 (en) 2000-01-13 2002-10-15 Midtronics, Inc. Alternator tester
US6225808B1 (en) 2000-02-25 2001-05-01 Midtronics, Inc. Test counter for electronic battery tester
US7446536B2 (en) 2000-03-27 2008-11-04 Midtronics, Inc. Scan tool for electronic battery tester
US8513949B2 (en) 2000-03-27 2013-08-20 Midtronics, Inc. Electronic battery tester or charger with databus connection
US7598744B2 (en) 2000-03-27 2009-10-06 Midtronics, Inc. Scan tool for electronic battery tester
US7728597B2 (en) 2000-03-27 2010-06-01 Midtronics, Inc. Electronic battery tester with databus
US6586941B2 (en) 2000-03-27 2003-07-01 Midtronics, Inc. Battery tester with databus
US7398176B2 (en) 2000-03-27 2008-07-08 Midtronics, Inc. Battery testers with secondary functionality
US8237448B2 (en) 2000-03-27 2012-08-07 Midtronics, Inc. Battery testers with secondary functionality
US9052366B2 (en) 2000-03-27 2015-06-09 Midtronics, Inc. Battery testers with secondary functionality
US7924015B2 (en) 2000-03-27 2011-04-12 Midtronics, Inc. Automotive vehicle battery test system
US8872516B2 (en) 2000-03-27 2014-10-28 Midtronics, Inc. Electronic battery tester mounted in a vehicle
US6967484B2 (en) 2000-03-27 2005-11-22 Midtronics, Inc. Electronic battery tester with automotive scan tool communication
US20050001626A1 (en) * 2000-03-27 2005-01-06 Bertness Kevin I. Modular electronic battery tester
US20050057256A1 (en) * 2000-03-27 2005-03-17 Midtronics, Inc. Scan tool for electronic battery tester
US6759849B2 (en) 2000-03-27 2004-07-06 Kevin I. Bertness Battery tester configured to receive a removable digital module
US7598743B2 (en) 2000-03-27 2009-10-06 Midtronics, Inc. Battery maintenance device having databus connection
US6998847B2 (en) 2000-03-27 2006-02-14 Midtronics, Inc. Electronic battery tester with data bus for removable module
US6304087B1 (en) 2000-09-05 2001-10-16 Midtronics, Inc. Apparatus for calibrating electronic battery tester
US6906523B2 (en) 2000-09-14 2005-06-14 Midtronics, Inc. Method and apparatus for testing cells and batteries embedded in series/parallel systems
US6519539B1 (en) 2000-09-29 2003-02-11 Hydrogenics Corporation Measurement of fuel cell impedance
US6816797B2 (en) 2000-09-29 2004-11-09 Hydrogenics Corporation System and method for measuring fuel cell voltage and high frequency resistance
US6388448B1 (en) 2001-03-13 2002-05-14 Actron Manufacturing Co. Electronic battery tester with normal/cold test modes and terminal connection detection
US6384608B1 (en) 2001-03-13 2002-05-07 Actron Manufacturing Co. Battery tester using internal resistance to measure a condition of a battery
US6417669B1 (en) 2001-06-11 2002-07-09 Keith S. Champlin Suppressing interference in AC measurements of cells, batteries and other electrical elements
US7015674B2 (en) 2001-06-22 2006-03-21 Midtronics, Inc. Booster pack with storage capacitor
US7479763B2 (en) 2001-06-22 2009-01-20 Midtronics, Inc. Apparatus and method for counteracting self discharge in a storage battery
US7501795B2 (en) 2001-06-22 2009-03-10 Midtronics Inc. Battery charger with booster pack
US6788025B2 (en) 2001-06-22 2004-09-07 Midtronics, Inc. Battery charger with booster pack
US6544078B2 (en) 2001-07-18 2003-04-08 Midtronics, Inc. Battery clamp with integrated current sensor
US6469511B1 (en) 2001-07-18 2002-10-22 Midtronics, Inc. Battery clamp with embedded environment sensor
US6466026B1 (en) 2001-10-12 2002-10-15 Keith S. Champlin Programmable current exciter for measuring AC immittance of cells and batteries
US6621272B2 (en) 2001-10-12 2003-09-16 Keith S. Champlin Programmable current exciter for measuring AC immittance of cells and batteries
US7363175B2 (en) 2001-10-17 2008-04-22 Midtronics, Inc. Query based electronic battery tester
US20050218901A1 (en) * 2001-10-17 2005-10-06 Bertness Kevin I Query based electronic battery tester
US6941234B2 (en) 2001-10-17 2005-09-06 Midtronics, Inc. Query based electronic battery tester
US7034541B2 (en) 2001-10-17 2006-04-25 Midtronics, Inc. Query based electronic battery tester
US7198510B2 (en) 2001-11-14 2007-04-03 Midtronics, Inc. Kelvin connector for a battery post
US6696819B2 (en) 2002-01-08 2004-02-24 Midtronics, Inc. Battery charge control device
US6930485B2 (en) 2002-03-14 2005-08-16 Midtronics, Inc. Electronic battery tester with battery failure temperature determination
US6906522B2 (en) 2002-03-29 2005-06-14 Midtronics, Inc. Battery tester with battery replacement output
US20030184306A1 (en) * 2002-03-29 2003-10-02 Bertness Kevin I. Battery tester with battery replacement output
US20040091759A1 (en) * 2002-05-17 2004-05-13 Harrington David Athol Methods and apparatus for indicating a fault condition in fuel cells and fuel cell components
US20040046564A1 (en) * 2002-09-05 2004-03-11 Klang James K. Battery test outputs adjusted based upon battery temperature and the state of discharge of the battery
US7081755B2 (en) 2002-09-05 2006-07-25 Midtronics, Inc. Battery tester capable of predicting a discharge voltage/discharge current of a battery
US7723993B2 (en) 2002-09-05 2010-05-25 Midtronics, Inc. Electronic battery tester configured to predict a load test result based on open circuit voltage, temperature, cranking size rating, and a dynamic parameter
US7012433B2 (en) 2002-09-18 2006-03-14 Midtronics, Inc. Battery tester upgrade using software key
US7148654B2 (en) 2002-12-03 2006-12-12 Hydrogenics Corporation Method and apparatus for monitoring fuel cell voltages
US20040150405A1 (en) * 2002-12-03 2004-08-05 Stephen Burany Method and apparatus for monitoring fuel cell voltages
US6781382B2 (en) 2002-12-05 2004-08-24 Midtronics, Inc. Electronic battery tester
US7208914B2 (en) 2002-12-31 2007-04-24 Midtronics, Inc. Apparatus and method for predicting the remaining discharge time of a battery
US7619417B2 (en) 2002-12-31 2009-11-17 Midtronics, Inc. Battery monitoring system
US6888468B2 (en) 2003-01-22 2005-05-03 Midtronics, Inc. Apparatus and method for protecting a battery from overdischarge
US20040220752A1 (en) * 2003-02-04 2004-11-04 Hydrogenics Corporation System and method for measuring internal resistance of electrochemical devices
US7425832B2 (en) 2003-02-04 2008-09-16 Hydrogenics Corporation System and method for measuring internal resistance of electrochemical devices
US6891378B2 (en) 2003-03-25 2005-05-10 Midtronics, Inc. Electronic battery tester
US6933727B2 (en) 2003-03-25 2005-08-23 Midtronics, Inc. Electronic battery tester cable
US20040251907A1 (en) * 2003-06-11 2004-12-16 Kalley Terrence D. Part tester and method
US7129706B2 (en) * 2003-06-11 2006-10-31 Bright Solutions, Inc. Part tester and method
US7408358B2 (en) 2003-06-16 2008-08-05 Midtronics, Inc. Electronic battery tester having a user interface to configure a printer
US6913483B2 (en) 2003-06-23 2005-07-05 Midtronics, Inc. Cable for electronic battery tester
US7319304B2 (en) 2003-07-25 2008-01-15 Midtronics, Inc. Shunt connection to a PCB of an energy management system employed in an automotive vehicle
US8164343B2 (en) 2003-09-05 2012-04-24 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US9255955B2 (en) 2003-09-05 2016-02-09 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US9018958B2 (en) 2003-09-05 2015-04-28 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US7154276B2 (en) 2003-09-05 2006-12-26 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US8674711B2 (en) 2003-09-05 2014-03-18 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US6919725B2 (en) 2003-10-03 2005-07-19 Midtronics, Inc. Electronic battery tester/charger with integrated battery cell temperature measurement device
US7977914B2 (en) 2003-10-08 2011-07-12 Midtronics, Inc. Battery maintenance tool with probe light
US20050077904A1 (en) * 2003-10-08 2005-04-14 Midtronics, Inc. Electronic battery tester with probe light
US7595643B2 (en) 2003-11-11 2009-09-29 Midtronics, Inc. Apparatus and method for simulating a battery tester with a fixed resistance load
US7116109B2 (en) 2003-11-11 2006-10-03 Midtronics, Inc. Apparatus and method for simulating a battery tester with a fixed resistance load
US7598699B2 (en) 2004-02-20 2009-10-06 Midtronics, Inc. Replaceable clamp for electronic battery tester
US7119686B2 (en) 2004-04-13 2006-10-10 Midtronics, Inc. Theft prevention device for automotive vehicle service centers
US7777612B2 (en) 2004-04-13 2010-08-17 Midtronics, Inc. Theft prevention device for automotive vehicle service centers
US7642786B2 (en) 2004-06-01 2010-01-05 Midtronics, Inc. Battery tester capable of identifying faulty battery post adapters
US7772850B2 (en) 2004-07-12 2010-08-10 Midtronics, Inc. Wireless battery tester with information encryption means
US7425833B2 (en) 2004-07-22 2008-09-16 Midtronics, Inc. Broad-band low-inductance cables for making Kelvin connections to electrochemical cells and batteries
US7106070B2 (en) 2004-07-22 2006-09-12 Midtronics, Inc. Broad-band low-inductance cables for making Kelvin connections to electrochemical cells and batteries
US8963550B2 (en) 2004-08-20 2015-02-24 Midtronics, Inc. System for automatically gathering battery information
US8344685B2 (en) 2004-08-20 2013-01-01 Midtronics, Inc. System for automatically gathering battery information
US8436619B2 (en) 2004-08-20 2013-05-07 Midtronics, Inc. Integrated tag reader and environment sensor
US9496720B2 (en) 2004-08-20 2016-11-15 Midtronics, Inc. System for automatically gathering battery information
US8704483B2 (en) 2004-08-20 2014-04-22 Midtronics, Inc. System for automatically gathering battery information
US8442877B2 (en) 2004-08-20 2013-05-14 Midtronics, Inc. Simplification of inventory management
US20070259256A1 (en) * 2004-11-29 2007-11-08 Jean-Marc Le Canut Systems and methods for detecting and indicating fault conditions in electrochemical cells
US7545146B2 (en) 2004-12-09 2009-06-09 Midtronics, Inc. Apparatus and method for predicting battery capacity and fitness for service from a battery dynamic parameter and a recovery voltage differential
US20060125482A1 (en) * 2004-12-09 2006-06-15 Midtronics, Inc. Apparatus and method for predicting battery capacity and fitness for service from a battery dynamic parameter and a recovery voltage differential
US7710119B2 (en) 2004-12-09 2010-05-04 Midtronics, Inc. Battery tester that calculates its own reference values
US7498767B2 (en) 2005-02-16 2009-03-03 Midtronics, Inc. Centralized data storage of condition of a storage battery at its point of sale
US7791348B2 (en) 2007-02-27 2010-09-07 Midtronics, Inc. Battery tester with promotion feature to promote use of the battery tester by providing the user with codes having redeemable value
US7940053B2 (en) 2007-02-27 2011-05-10 Midtronics, Inc. Battery tester with promotion feature
US20080252437A1 (en) * 2007-04-16 2008-10-16 Midtronics, Inc. Battery run down indicator
US7808375B2 (en) 2007-04-16 2010-10-05 Midtronics, Inc. Battery run down indicator
US8306690B2 (en) 2007-07-17 2012-11-06 Midtronics, Inc. Battery tester for electric vehicle
US9335362B2 (en) 2007-07-17 2016-05-10 Midtronics, Inc. Battery tester for electric vehicle
US9274157B2 (en) 2007-07-17 2016-03-01 Midtronics, Inc. Battery tester for electric vehicle
US8203345B2 (en) 2007-12-06 2012-06-19 Midtronics, Inc. Storage battery and battery tester
US20090192726A1 (en) * 2008-01-25 2009-07-30 Eveready Battery Company, Inc. Electrochemical Composition Detection Device and Method Thereof
US9588185B2 (en) 2010-02-25 2017-03-07 Keith S. Champlin Method and apparatus for detecting cell deterioration in an electrochemical cell or battery
US9425487B2 (en) 2010-03-03 2016-08-23 Midtronics, Inc. Monitor for front terminal batteries
US9229062B2 (en) 2010-05-27 2016-01-05 Midtronics, Inc. Electronic storage battery diagnostic system
US9419311B2 (en) 2010-06-18 2016-08-16 Midtronics, Inc. Battery maintenance device with thermal buffer
US9201120B2 (en) 2010-08-12 2015-12-01 Midtronics, Inc. Electronic battery tester for testing storage battery
US8738309B2 (en) 2010-09-30 2014-05-27 Midtronics, Inc. Battery pack maintenance for electric vehicles
RU2536780C1 (en) * 2010-12-10 2014-12-27 Ниссан Мотор Ко., Лтд. Device and method to measure inner resistance for packaged battery
US9182430B2 (en) * 2012-03-22 2015-11-10 Continental Automotive Gmbh Device and method for measuring a value of a resistor
US20130249575A1 (en) * 2012-03-22 2013-09-26 Continental Automotive Gmbh Device and method for measuring a value of a resistor
US9851411B2 (en) 2012-06-28 2017-12-26 Keith S. Champlin Suppressing HF cable oscillations during dynamic measurements of cells and batteries
US9244100B2 (en) 2013-03-15 2016-01-26 Midtronics, Inc. Current clamp with jaw closure detection
RU2531062C1 (en) * 2013-03-26 2014-10-20 Открытое акционерное общество "Научно-производственное объединение измерительной техники" Device of accumulator battery control
US9312575B2 (en) 2013-05-16 2016-04-12 Midtronics, Inc. Battery testing system and method
US9923289B2 (en) 2014-01-16 2018-03-20 Midtronics, Inc. Battery clamp with endoskeleton design
US20160020618A1 (en) * 2014-07-21 2016-01-21 Ford Global Technologies, Llc Fast Charge Algorithms for Lithium-Ion Batteries
WO2016071213A1 (en) * 2014-11-03 2016-05-12 Bayerische Motoren Werke Aktiengesellschaft Circuit arrangement and method for determining the impedance of a test battery

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